Medical catheters having a balloon mounted thereon are useful in a variety of medical procedures. Balloon catheters may be used to widen a vessel into which the catheter is inserted by dilating the blocked vessel, such as in an angioplasty procedure. Balloon catheters may also be used to expand and/or seat a medical device such as a stent or graft at a desired position within a body lumen. In all of these applications, fluid under pressure may be supplied to the balloon through an inflation lumen in the catheter, thereby expanding the balloon.
It is essential in the manufacture of balloon catheters to properly seal the balloon to the catheter. The seal must be able to withstand the high pressures to which it is subjected on inflation of the balloon. A poor seal may result in leakage of inflation fluid and inability to achieve the desired pressure or even rapid loss of pressure and deflation of the balloon. In addition, it is desirable to shape the outside surface of the weld region to provide a smooth transition from the outer shaft to the balloon.
Also, in general, dilatation balloon catheters are preferably designed to optimize pushability, trackability, crossability, and torque transmission to the distal catheter end as such is applied to the proximal end of the catheter. Trackability may be defined for the purpose of this application as the ability to navigate tortuous vasculature. That is, the distal portion of the catheter preferably tracks the guide wire through small tortuous vessels to reach the area to be treated. A more flexible distal portion is known to improve such trackability. Thus, it may be desirable to provide a catheter shaft with material properties as well as a method of bonding the balloon to the catheter shaft to improve flexibility.
The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §1.56(a) exists.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.